It will convert your images. But what you have most likely done is you have browsed and tried to show the contents of the folder where your images are located. That won't work. Just choose the folder, don't open it, and then click to convert after making sure all your options are correct. The prompt tells you to select the FOLDER, not the images.
I have created a folder for a few sample NEF's and it does not work
OK, you were right... I was wrong... you are good looking... I am not so attractive.
The problem I was having was that I created a new folder within a folder. I just needed to go to Nikon Transfer (folder) and pick the dated folder that I wanted.
Thank you for helping me out. It is nice since DNG offers NO troubleshooting (so convenient)!!
Yes, but at least the DNG converter is free.